PAC07 - List of Authors (Okamura, M.)

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Okamura, M.

Paper	Title	Page
TUPAN064	Use of Solidified Gas Target to Laser Ion Source	1535
	J. Tamura RLNR, Tokyo T. Kanesue Kyushu University, Department of Applied Quantum Physics and Nuclear Engineering, Fukuoka M. Okamura BNL, Upton, Long Island, New York
	We examined a laser produced neon plasma as part of a future laser ion source. The ion source is capable of generating highly ionized particles and high intensity beams by irradiating a solid target with a pulsed laser. Rare gases, which are in gas state at room temperature, need to be cooled to solid targets for laser irradiation. We generated solid neon targets by equipping our laser ion source chamber with a cryogenic cooler. This method will generate high current rare gas beams.
TUPAS083	Design and Performance of the Matching Beamline between the BNL EBIS and an RFQ	1844
	J. G. Alessi, E. N. Beebe, J. Brodowski, A. Kponou, M. Okamura, A. I. Pikin, D. Raparia, J. Ritter, L. Snydstrup, V. Zajic BNL, Upton, Long Island, New York
	Funding: Work performed under the auspices of the U. S. Department of Energy and the U. S. National Aeronautics and Space Administration. A part of a new EBIS-based heavy ion preinjector, the low energy beam transport (LEBT) section between the high current EBIS and the RFQ is a challenging design, because it must serve many functions. In addition to the requirement to provide an efficient matching between the EBIS and the RFQ, this line must serve as a fast switchyard, allowing singly charged ions from external sources to be transported into the EBIS trap region, and extracted, highly charged ions to be deflected to off-axis diagnostics (time-of-flight, or emittance). The space charge of the 5-10 mA extracted heavy ion beam is a major consideration in the design, and the space charge force varies for different ion beams having Q/m from 1-0.16. The line includes electrostatic lenses, spherical and parallel-plate deflectors, magnetic solenoid, and diagnostics for measuring current, charge state distributions, emittance, and profile. A prototype of this beamline has been built, and results of tests will be presented.
THPAN033	Design Study of the Dipole Magnet for the RHIC EBIS High Energy Transport Line	3301
	T. Kanesue Kyushu University, Department of Applied Quantum Physics and Nuclear Engineering, Fukuoka M. Okamura, D. Raparia, J. Ritter BNL, Upton, Long Island, New York J. Tamura RLNR, Tokyo
	The design studies of the dipole magnet for EBIS HEBT line is proceeding. The RHIC EBIS is a new high current highly charged heavy ion preinjector for RHIC. The dipole magnet discussed in this paper will be used to guide the beam to existing heavy ion injection line to Booster. A total of 145 degrees bend is provided by two identical dipole magnets with a slit between these magnets to pass only intended charge state ions. Also this magnet has a hole in the side wall to pass the beam from the existing Tandem Van de Graaff. The performance of this magnet calculated by TOSCA and the results of the particle tracking calculation are described.
FRXAB02	Review of Laser Driven Sources for Multi-charged Ions	3761
	M. Okamura BNL, Upton, Long Island, New York A. Kondrashev ANL, Argonne, Illinois
	Funding: This work was supported by the U. S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC-02-06CH11357 Laser beams have been widely used in the accelerator field for various applications. Here, we focus on ion beam production usage as an ion source. The laser ion source (LIS) already has about thirty years history and was developed for providing pulsed beam to synchrotrons. Since 2000 we have concentrated on the use of the high brightness of induced laser plasma to provide intense highly charged ions efficiently. To take advantage of the intrinsic density of the plasma, Direct Plasma Injection Scheme (DPIS) has been developed. The induced laser plasma has initial expanding velocity and can be delivered directly to the RFQ. The presentation will discuss general features of the laser ion sources and advantages of the DPIS.
	Slides
THPAS103	Design of a Thin Quadrupole to be Used in the AGS Synchrotron	3723
	N. Tsoupas, L. Ahrens, R. Alforque, M. Bai, K. A. Brown, E. D. Courant, J. W. Glenn, H. Huang, A. K. Jain, W. W. MacKay, M. Okamura, T. Roser, S. Tepikian BNL, Upton, Long Island, New York
	Funding: Work supported by the US Department of Energy The AGS synchrotron employs two partial helical snakes* to preserve the polarization of the proton beam during acceleration in the AGS. The effect of the helical snakes on the beam optics is significant at injection energy, with the effect greatly diminishing early in the acceleration cycle. In order to compensate for the effect of the snakes on the beam optics, we have introduced eight compensation quadrupoles in straight sections of the AGS at the proximity of the partial snakes. At injection the strength of these eight quads is set at a high value but ramped down to zero when the effect of the snakes diminishes. Four of the compensation quadrupoles had to be placed in very short straight sections therefore had to be 'thin' with a length of ~30 cm. The 'thin' quadrupoles were laminated and designed to minimize the strength of the dodecoupole harmonic. The thickness of the lamination was also calculated** to keep the ohmic losses generated by the eddy currents in the laminations below an acceptable limit. Comparison of the measured and calculated harmonics will be presented and the ohmic losses due to the eddy currents, as a function of time during rumping will be discussed. * H. Huang, et al., Proc. EPAC06, (2006), p. 273.** OPERA computer code. Vector Fields Inc.